Accession Number : AD0704550

Title :   ELECTRON OPTICAL STUDIES OF HETEROEPITAXIAL GROWTH OF BETA SILICON CARBIDE LAYERS THROUGH MOLTEN METAL INTERMEDIATES.

Descriptive Note : Physical sciences research papers,

Corporate Author : AIR FORCE CAMBRIDGE RESEARCH LABS L G HANSCOM FIELD MASS

Personal Author(s) : Comer,Joseph J. ; Berman,Irvin

Report Date : MAR 1970

Pagination or Media Count : 22

Abstract : Beta silicon carbide has the potential of becoming an important semiconductor device material for hazardous military environments such as high temperature and radiation. This report is concerned with a study of the growth of thin single crystal films of beta silicon carbide through molten metal intermediates. Thin films of nickel, cobalt, chromium and iron were deposited by vacuum deposition on to the (0001) faces of single crystals of alpha silicon carbide. Then heteroepitaxial layers of beta silicon carbide were deposited through the molten metal films by the hydrogen reduction of methyltrichlorosilane. The deposited films were studied by electron microscopy, electron diffraction and electron beam microprobe analysis to determine the growth mechanism and to arrive at optimum conditions for heteroepitaxial growth. From the results obtained it was concluded that nickel and cobalt were equally effective in promoting epitaxial growth. Films of nickel only 20A in thickness were as effective as those up to 300A. Results with chromium and iron were disappointing for different reasons. Chromium did not etch the substrate surface uniformly because of poor wetting. With iron, whisker growth of beta silicon carbide occurred at the surface. Although in many respects the growth of mechanism resembled that of the vapor-liquid-solid method, certain differences were observed which make the actual growth mechanism using nickel and cobalt films still uncertain. (Author)

Descriptors :   (*SILICON CARBIDES, EPITAXIAL GROWTH), SINGLE CRYSTALS, ELECTRON MICROSCOPY, ELECTRON DIFFRACTION, METAL FILMS, NICKEL, COBALT, CHROMIUM, IRON, FILMS

Subject Categories : Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE